According to the Star Trek: Deep Space Nine Technical Manual, 25 isotons is the maximum theoretical yield of a matter-antimatter reaction in photon torpedoes and that quantum torpedoes have at least twice the yield at 50+ isotons. (p. 85) These figures are not compatible with the canonical statements in "Scorpion, Part II" of 200 isotons as the yield of a class-6 photon torpedo warhead and in Star Trek Into Darkness of 320 isotons as the yield of a class-12 photon torpedo. As with most other measures used in Star Trek there are no direct conversions to real world measures given.

In Star Trek: The Next Generation Technical Manual a figure of 1.5 kg of antimatter is given as the amount of warhead material carried by a standard photon torpedo. (p. 129) Using standard physics calculations a direct 1:1 detonation would generate 64.4 megatons of energy. Warhead materials are however premixed to achieves the level of destructive force of an antimatter pod rupture containing 100 cubic meters of antideuterium. (p. 69) Antimatter is stored as liquid or slush on starships. (p. 68) Density of mere liquid antideuterium is around 160 kg per cubic meter. According to this comparison the destructive effect in the high annihilation rate energy release would be comparable to the effects of a 690 gigaton blast. Furthermore it is not clear if the 1.5 kg should be compared to the 200 - 320 isoton figures given on screen later on, or the 25 isoton figure given in the Star Trek: Deep Space Nine Technical Manual reference book to make a conversion.